3TGTE Issues

[Hulk]

Ok, earth points sanded now. I've also Earthed the knock sensor wire to see how that goes today.

I will check the timing on the weekend when I have more time to take the cam cover off.

Just noticed a dodgy looking plug on injection side. Situated down between injectors 2 & 3 (centre). Seems to plug into something electrical and square. Wotzat?

[3t-RA40]

It's something similar to an idle air control valve. Not sure of its proper name but that's it job.
Cheers,
Neil.

[TA22 GT]

Yep, it allows more air on a cold start. That will be a 2 pin plug that simply powers a small coil when the ignition is on. Once on it heats the coil which slowly closes the air bypass off.
Even if that plug is faulty it is very unlikely to be your problem.

Cheers,
Simon

[Hulk]

Ok cam timing seems ok.

maybe check that the VR sensor in the dizzi doesn't have anything loose?

Anything I should watch out for if I pull apart the diaphragm on top of the dizzy?

[Ta22boy]

hey guys,
Sorry to jack the thread but i didnt think it was worth making another one when you have similar problems to me, but mine is a constant miss that seems to be a fueling issue, but i have also realised my car is only running on the cold start injector, so any help as why the injectors arent firing would be appreciated. On thing i thought of though, my alternator hasnt been charging and the batt only had 11.5V running the fuel pumps,thermo,injectors etc but do the the injectors need a certain voltage on the 3tgte to turn on?
Any help would be really appreciated

Cheers
Scott

[AE25]

i'll suggest a few things to check and go from there...
#2: when it cuts out.. you say you disconnected the ecu.. crank it which fires for a second.. then reconnect the ecu and its back to normal.. this could suggest a couple things to me... one is possibly flooding when it cuts out? as disconnecting the ecu theoretically will stop the injectors pulsing but not the spark. so your effectively unplugging the injectors and burning off any fuel left in the engine. though i would think you'd have to crank it for a while without fuel before wet plugs would fire again??
OR possibly the afm is jamming in one spot.. and when starting it, the vibrations or slow valve pulses are freeing it up. this could also explain the flat spots in the revs as a small throttle movement is not freeing it up and therefore leaning it out... until a large throttle movement happens.
i'd suggest to push the afm flap by hand and see if there's any tight spots. or check inside the afm for any weird stuff on the black resistance pads where the pin slides across it. If the afm cover has never been pulled off then i'd doubt this be the case. (or test with a multimeter across the plug pins for resistance to see that it increases/decreases smoothly when pushing the flap).
next time the engine cuts out and wont start.. tap the afm instead of disconnecting the ecu and see if that helps it restart.

the fuel cut can do horrible things when running higher boost and it's easily taken out of the system by taking the vacuum hose off so it doesnt see any pressure. i was forced to disconnect it once a 2.5" exhaust was fitted as it was boost creeping past the 0.7bar or whatever the cutoff point.
i see no reason to disconnect the fuel enrichment switch unless you're running too rich under boost.
as to injectors.. this is a never ending problem for me.. mainly leaks. i had 3 sets flowed and only one set was not either leaking or had completely failed. and months later my engine was running rough on idle and part throttle and found more injectors leaking. i found you can simply blow compressed air thru them to see if they're leaking. (into a bowl of water to see small leaks) and if they're not working.. give it a tap on some wood or something as that can sometimes free up the pintle. newer injectors would be the go.. std ones are 22+years old remember.

what exactly is ticking when you wiggle the ecu plug? ticking is usually a relay or solenoid (injector). but most relays for the engine are off when key is on acc. could there be a crossed wire some where nearby? and what could be causing the tick by wiggling the plug??? have you got a dry plug connection, frayed wire or cracked ecu circuit board maybe?

noisey pump?? what kind of noise? where is the pump mounted?
poor fuel flow will cause flat spots for sure.
when i first ran my 3tgte.. i used a 2tgeu fuel pump and the engine felt weak which i wasnt too impressed with and suspected the pump .. so chucked in a v8 pump from my other car and the engine perked up nicely noise can often be air sucked thru the pump.. you have got gas in there right??????????????!!!!!!!!!!!!!!!!!!!!!!!!!

how are you seeing air bubbles after throttle off? is that with bonnet up and no radiator cap.. revving it etc. when was the last time you gave it a compression test? is there any water leaks on the engine?

the pic you showed is the cold idle up valve. it's operated with a bimetallic strip which closes the valve when it gets warm. if the plug is disconnected then the heat from the engine also eventually closes it. i find these valves always crap out. the bimetallic strip loses its movement when hot. when it fails.. it just gets stuck at a certain spot so you'll end up with a high idle rpm once engine is warm.

ta22boy: start a new thread haha. um your engine wont 'run' on the cold start injector.. it only opens for 5seconds or so. disconnect the plug from the cold start injector to find out! how bout starting a thread and explaining everything you know about the problem so people can suggest a fix.. that way its directed to your problem specifically.
also i had a dead alternator for a week, driving 15mins to work everyday and charging battery over night.. the engine started misfiring around 6v (not boosting it to be safe) and dies at about 4v.
so much for 'Post Quick Reply' lol

[Ta22boy]

cheers
will start new thread and give you the full story

[Hulk]

Whoa.................. I'm gonna be busy.

Thanks for that AE25

[Hulk]

.


TA22boy, keep an eye on this thread. I often subscribe to tech threads that are similar to problems I have.
e.g - There's a 3SGTE 30% power loss thread that I'm keeping tabs on because the problem sounds similar, but different engine.

Perhaps it's time we started a dedicated 3TGTE thread like the 18RG and 2T/G threads that are on here.


.

[Mundoolun]

It sounds like maybye a blown headgasket or crack in cyclinder head. I now the previous owner never upgraded the radiator to a tripple core and it would boil even after five minutes of gentle driving. Also if the injectors are leaking get them fixed immmeaditely as it can cause a rather nasty fire. Have them clean a re o-ringed last time I had this done was a paltry $140 bucks with flow bench report . Also the fuel system is rather undersized as it doesn't even have a surge tank or primer pump only a single vl turbo main feed pump could be fuel starvation. Also fit a blow off valve as the last time Jake took me for a spin the poor old turbo was surging all the time and sometimes even shuddered on deaceleration as he upped the boost due to front mount intercooler and bleed valve.

[Hulk]

Sweeeeeeettt !! Tell me more!

[Hulk]

I will have a compression tester and fuel pressure gauge tommorow.

What compression is healthy for a 3TGTE?

Edit - Couldn't wait so I went to mates house and picked up the compression tester.

132 - 135 psi across all 4.

Is this good?

[Ta22boy]

hey Hulk, does your car get hot even sitting at idle, or when you go for a gentle drive? if its not still overheating constantly still then i wouldnt think it would be the head gasket or have a cracked head unless you have noticed a lot of bubbles in your radiator even at idle? anyways if your fuel pump is noisy then generally they are on there way out, source a different pump but one would think a vl pump could flow enough for a 3tgte as a lot of people use the exact same set-up including me and it works well...
Other then that i would be checking the fuel pressure and flow when you get to these flat spots and then defiantly have someone check out the ECU plug and wire,relays surrounding it for a short,bad earth ETC as this may be the cause of your problem but other then that if your engine is knocking at those rpm's it will cause a flat spot due to retarding the ignition, all food for thought but hope you find something soon and both our nightmares end sometime soon...lol

Cheers

[Hulk]

I've never noticed any overheating problems since I've had the car. First thing I did when I bought it was a coolant and oil change.

[Ta22boy]

hey Hulk, its doubtful its a blown headgasket then, and even if it was you would have other problems arising from this...such as oily coolant, water in the sump, bubbles in the radiator at all times, excessive overheating, using lots of water....i mean theres quite a few things not always all together but usually if you have one or two of these then you have a bad head gasket, but i think you have something wrong with your electrics, maybe as well as a slight fuel flow issue, but if that was the case, i would think as soon as you went to accelerate the car would feel like its surging, rather then just go flat at certain RPM's...
Take it to someone who knows there electrics and have them have a look and see what you find....Where in QLD are you located?

Cheers
Scott